Certain processes for the preparation of urea or phenol and formaldehyde beads have been known in the art. For example, Canadian Patent No. 909,433 is directed to a process of producing a phenol-formaldehyde resin which comprised reacting from 0.6 to 1 mole of formaldehyde with each mole of para-substituted phenol in the presence of an effective amount of an acidic catalyst and a hydrophobic organic solvent capable of forming an azeotrope with water, dissolving the remaining polymer in an aqueous alkali solution which separates any remaining organic solvent from the solution, and then adding an acid to the solution to precipitate the polymer. The polymer provided here must be crushed in order to make the composition a useful powder.
U.S. Pat. No. 3,516,941 is directed to microcapsules which comprise an organic liquid film enclosed by a strong, impermeable shell of urea-formaldehyde polymer. These microcapsules are produced by dispersing and maintaining the film material as finely divided particles in an aqueous, water-soluble urea-formaldehyde precondensate solution substantially free of carboxymethyl cellulose and other wetting agents, while polymerizing the free condensate by acid catalyst for at least one hour in a pH range of about 1 to about 5.
Canadian Patent No. 887,694 relates to certain solid inert flatting or texturing agents consisting pf particulate solids with particle diameters from 1 to 700 microns insoluble in organic media and comprising greater than 75 percent but less than 90 percent by weight of a pigment dispersed in a polymeric binder, further characterized in that the volume concentration of the pigment in the polymeric binder is less than 82 percent and the pigment has an oil absorption of 90 maximum. It will be noted that these agents require the inclusion of a pigment therein.
Canadian Patent No. 855,768 is directed to a pigment extender composition comprising fully polymerized urea-formaldehyde particles having dispersed therein 15 to 35 percent by volume of TiO.sub.2 particles, the mole ratio of the urea to formaldehyde in these particles being substantially one to one, and the particles ranging in size from greater than one micron up to 30 microns, preferably from 2 to 20 microns.